This invention is generally directed to an apparatus for collecting and/or growing protected biological specimens. It is particularly directed to a novel structure for obtaining, transporting and/or growing biological specimens which are completely protected from contamination at all times after initial capture.
The problem of protecting a biological specimen from contamination during and after its initial capture is an old one. That is, it is well known that unless special precautions are taken, a given biological specimen may inadvertently become contaminated during the collection process and/or during transfer of the collected specimen to a growing medium or the like. Once thus contaminated, the worth of the specimen for diagnostic or research purposes may be greatly reduced or even eliminated.
Deep cavity cultures as well as shallow cavity cultures (e.g. abscesses, surgical incisions, etc.) are an everyday necessity in medicine, both human and veterinary. The results of these cultures must be accurate in order for a doctor to be certain of the condition and of the type of treatment necessary, if any. The uses vary from remedial to lifesaving, to status, as in the case of many veterinary uses. One such veterinary use would be in determining the bacterial count and type in the uterus of an equine mare prior to breeding.
Since the specimens are obtained in non-sterile environments, for the most part, it is imperative that the specimen be protected from contamination from the outer extremities of these cavities, as well as from air, which, for example, generally contains bacteria. Any contamination with bacteria from the air or outer extremities of the cavity would provide false or misleading diagnosis of the condition sought.
Certain prior attempts have been made to minimize contamination by inserting a device including two tubes, one within the other, to the desired depth in the cavity. Upon insertion, the inner tube, or rod is extended past the end of the outer tube, and a cotton swab contained on the end of the inner tube is saturated with mucosa from the walls of the cavity at the desired point. Upon saturation, the inner tube is withdrawn into the outer tube and then both withdrawn as a unit to the outside air.
For the bacteria contained in the mucosa on the swab to survive and grow, they must be placed in a growth environment medium, most generally in the form of a sterile liquid or gel. This is generally in a test tube like container. The procedure is to remove the mucosa saturated swab from the outer tube and place it in the tube of growth medium, cutting or breaking off the tube and placing a stopper in the tube. It is then transported to the lab where the growing culture is identified by laboratory techniques.
Typical prior art approaches to this problem are illustrated in the following prior issued U.S. patents:
U.S. Pat. No. 3,513,830--Kalayjian (1970) PA1 U.S. Pat. No. 4,136,680--Southworth (1979) PA1 U.S. Pat. No. 4,235,244--Abele et al. (1980) PA1 U.S. Pat. No. 3,394,699--Koett (1968) PA1 U.S. Pat. No. 3,674,007--Freis (1972) PA1 U.S. Pat. No. 3,800,781--Zaluchi (1974) PA1 U.S. Pat. No. 3,995,618--Kingsley et al. (1976) PA1 U.S. Pat. No. 4,023,559--Gaskell (1977) PA1 U.S. Pat. No. 4,157,709--Schuster (1979) PA1 U.S. Pat. No. 4,184,483--Greenspan (1980) PA1 U.S. Pat. No. 4,223,093--Newman et al. (1980)
Kalayjian and Abele et al. are both typical of prior art approaches where a biological specimen collecting swab attached to the end of an elongated rod is protected within a outer hollow tube structure temporarily sealed with a cap-like seal at its distal end. In use, the sealed distal end of the rod and tube assembly is projected into an internal body organ or the like where the desired biological sample naturally resides. Thereafter, the rod is extended to displace the seal at the distal end of the tube and to expose the swab at the desired biological site. After the specimen has been collected on the swab, it is then withdrawn into the outer protective tube and the entire assembly is withdrawn from the body organ or the like. Later, the rod with the biological swab is transferred from the protective tube to a culture growth medium or the like in another structure. As will be appreciated, many types of bacteria can be seriously contaminated, and/or killed, by even brief exposure to oxygen in the air, or other gaseous, liquid or solid contaminants that may be encountered whenever the swab is not in a completely protected environment.
Southworth provides an apparatus which attempts to more completely protect the biological specimen. For example, the distal end of the outer hollow protective tube includes a hinged cap assembly that is designed to provide some protection both before and after the swab is used for collecting a biological specimen. Furthermore, provisions are made for withdrawing the collected specimen directly into an enlarged anterior chamber where a culture growth medium or the like is provided. However, the hinged protective cap structure in Southworth is not believed to provide true isolation or absolute protection from the ambient environment and, in any event, the overall multi-part apparatus appears to be relatively complex and expensive.
The remaining patents referenced above are typical of other types of instruments for obtaining biological specimen. However, none of them are believed to describe a structure which may be used for collecting the biological specimen and thereafter transporting it to a desired culture growth medium or the like in a completely protected environment, or in an anaerobic state.
To a large degree, problems noted above have been solved by the inventions described in commonly assigned prior U.S. Pat. Nos. 4,653,510 and 4,485,824, which disclose specimen collecting devices incorporating relatively movable inner rod and outer tubular elements which enable biological specimens to be collected at the natural biological site and thereafter maintained in a completely protected environment at all times while being transported away from the natural biological site and into the presence of desired biological growth materials, transport materials, release agents, etc.
There are instances, however, where the specimen collectors described in the above identified commonly assigned patents are not wholly satisfactory. For example, where a doctor is trying to touch a small lesion (less than 1/4 inch in diameter) or a puss pocket in a wound, the front seal mounted forward of the swab (for sealing the inner rod and outer tube when the swab attached to the inner rod is fully retracted into the outer tube) may prevent him from obtaining a sample. Similarly, it may be difficult to touch areas in the back of the throat or trachea because of the presence of the front seal, and to twist or bend the front seal away from the area to be touched, can cause patient discomfort.
In other instances where the swab is surrounded by body fluids or tissues on which there is a large surface area, the specimen collectors as described in the above patents do not present this problem. However, in those special situations mentioned above, the front seal located forward of the swab does in fact limit the specimen sampling.
This present invention relates to a novel and unique specimen collector which also utilizes a swab connected to an inner rod movable out of and into an outer tubular element. In this invention, the forward seal is attached to the outer tube of the collector which allows the inner rod and attached swab to pierce this unique seal design for specimen collecting, and then to be withdrawn back into a protected environment within the outer tube without contamination.
Thus, in one exemplary embodiment of the invention, a specimen collector includes an elongated outer hollow cylindrical tubular member having a forward end and a rearward end. An inner elongated rod having a forward and rearward end portions is slidably mounted within the outer tube. A specimen collector swab is mounted to the forward end of the inner rod, while a rearward extension including a gripping means is attached to the rearward end of the inner rod in order to effect sliding movement of the inner rod relative to the outer tube.
A coaxial space between the inner rod and the outer tube is divided axially by a plurality of seals. As already noted, a first or forward seal is provided at the forward end of the outer tube. A second seal is mounted at the forward end of the inner rod, just behind the specimen collector swab. A third seal is fixedly mounted to the inner surface of the outer tube and includes a centrally located aperture to permit the inner rod to move slidably therethrough. A fourth seal, similar to the third seal, may be mounted some distance behind the third seal and may also be fixed to the inner surface of the outer tube for preventing entry of contaminants that may be present on the inner rod from passing the third seal. If desired, a guide may be fixed to the rearward end of the inner rod just ahead of the rearward extension and finer loop. This guide has an outer diameter slightly less than the inner diameter of the outer tube so as to guide the rearward end of the inner rod in substantially straight line movement within the outer tube.
It is a significant feature of this invention that the first or forward seal mounted to the forward end of the outer cylindrical tube is openable to permit the specimen collector or swab to pass through the seal when the inner rod is moved forward relative to the outer tube. This first or forward seal has a rounded or dome-like forward portion and a rearward cylindrical portion which terminates in a rearward end. The rearward end incorporates means for attaching the forward seal within the forward end of the outer tube. The arrangement here is such that, when the swab element is positioned adjacent the first or forward seal, the latter cannot be separated from the outer tube.
The forward domed portion of the seal, in an exemplary embodiment, is divided into four substantially identical petal-like appendages, each of which is pivotably movable between open and closed positions and which originate in a relatively thickened base area where the forward domed portion joins with the relatively thinner rearward cylindrical portion. This thickened base portion is shaped to form a annular corner surface where it joins with an interior surface of each of the petal-like appendages.
Upon forward motion of the inner rod, the specimen collector or swab will first engage the above described annular corner or edge surfaces on the interior of the petal-like appendages to thereby push the latter to an open position. This unique construction of the seal, as further defined hereinbelow, insures that the specimen collector will not come into contact with any surfaces of the petal-like appendages which are otherwise exposed when the forward seal is in the open position.
The coaxial space between the forward seal and the second flexible seal creates a first forward chamber extending between the two seals. Similarly, the coaxial space between the second and third seals creates a second chamber, and because the second seal moves axially with the inner rod, the volume of the two chambers varies upon extension and/or retraction of the inner rod relative to the outer tubular member as in my previously described patents. A more detailed description of the seals and the function of the associated chambers will be provided hereinbelow.
It is a significant advantage of this invention that the specimen collector as described may be combined with a non-foamed, molded and sintered porous plastic swab element (additional details are provided further herein) which has been proven to be very effective in terms of its ability to pick up and release fluids quickly and uniformly.
Thus, in accordance with an exemplary embodiment of the invention, there is provided, broadly, a specimen collector which comprises an outer tubular member having a forward end including a forward edge, and a rearward end; an inner rod slidably received within the outer tubular member and having a swab element attached to a forward end thereof; a first seal mounted to the forward end of the outer tubular member comprising a forward portion including a plurality of appendages movable between closed and open positions, and a rearward portion received within the forward end of the outer tubular member such that the forward edge of the outer tubular member provides a fulcrum for movement of the appendages from the closed to the open position; and a second seal mounted on the inner rod behind the swab element.
In another aspect, the invention provides a specimen collector device comprising an outer tubular member having a forward edge and a rearward edge; an inner rod slidably received within the outer tubular member and having a swab element attached to a forward end thereof, the inner rod movable within the outer tubular rod between a retracted position where the swab element is located within the outer tubular member and an extended position where the swab element is located outside the tubular member; and at least one seal fixed to the outer tubular member adjacent the forward edge, the seal having a forward end portion including a plurality of pivotable appendages extending beyond the forward edge and movable between closed and open positions, and a rearward portion received within the outer tubular member rearward of the forward edge, the first seal having an interior thickened area between the forward and rearward portions, engageable by the swab element upon movement to its extended position.
In still another respect, the invention relates to a specimen collector comprising an outer tubular member having a forward end including a forward edge, and a rearward end; an inner rod slidably received within the outer tubular member and having a non-foamed, molded porous plastic swab element attached to a forward end thereof, and a finger grip attached to a rearward end thereof to thereby enable the swab element to be moved out of and back into the outer tubular member between extended and retracted positions; a first seal mounted to the forward end of the outer tubular member comprising a forward portion including a plurality of appendages movable between closed and open positions, and a rearward portion received within the forward end of the outer tubular member such that the forward edge of the outer tubular member provides a fulcrum for movement of the appendages from the closed to the open position; a second seal mounted on the inner rod behind the swab element; and a third seal mounted within and fixed to the outer tubular member rearwardly of the second seal and having an aperture therein to permit the inner rod to slide therethrough.
Additional objects and advantages of the subject invention will become apparent from the detailed description which follows.